1. Field of the Invention
The present invention is broadly concerned with an improved applicator/spreader apparatus useful in roofing operations for the spreading of viscous flowable materials such as asphaltic roofing mastics. More particularly, the invention pertains to applicator/spreader devices which employ a delivery bar with a pair of specially configured trailing brooms serving to spread and evenly apply roofing materials. The devices of the invention further preferably include a temperature gauge located in close adjacency to the delivery bar so as to allow the user to exercise a greater and more accurate degree of control for application and spreading operations.
2. Description of the Prior Art
Many industrial-type buildings constructed during the last 30 to 40 years were roofed with metallic decking panels. Such panels were normally secured by screws, bolts, or rivets penetrating the metal decking, these penetrations being sealed. Metal roofs of this type suffer from a number of disadvantages, including a tendency to leak, and poor thermal insulation qualities. Over the years, as these metal roofs have begun to wear out, the building owners are faced with the task of providing a replacement roof. Generally speaking, it is a very expensive proposition to remove the original metal decking, and replace it with new decking. Another alternative is to simply place a new metal deck atop the original deck. This is a problem inasmuch as the new metal roof imposes a significant dead load upon the structure of the building, which is particularly troublesome in the case of older buildings.
It has also been suggested in the past to provide a replacement built-up roof using the worn metal roof as a substrate. In such systems, preformed panels of expanded polystyrene, adapted to be placed over the contour of the original deck are employed. Such panels have rigid boards secured to the upper surfaces thereof, and are generally provided in 4'.times.4' or 4'.times.8' sections. With such built-up roofs, hot asphalt is initially applied to the decking, whereupon the preformed insulation panels are applied. At this point, a roofing membrane may be secured to the upper surface of the foam panels sections, followed by conventional lap joint sealing and finishing. In some of these prior built-up constructions, hot asphalt or existing mastics have been employed which include asphalt, mineral spirits, fibers and fillers. A problem with these roofs is that, in the event of a fire, the polystyrene foam readily melts and becomes flowable, and then drips into the building below with the asphalt. This can cause severe damage to the building and its contents, and indeed the fire insurance rates for a building having a built-up roof of this character are increased because of this hazard if insurable at all.
U.S. Pat. No. 5,358,347 describes a greatly improved built-up roofing system which overcomes many of the problems with prior replacement roofs. As an adjunct to the roofing system, the '347 patent also discloses an improved applicator apparatus for the application and spreading of roof mastics. This applicator employs an elongated, transversely extending delivery bar having a series of valve units along the length thereof, with trailing spreader chains designed to spread and apply mastic delivered from the bar. While applicator devices as shown in the '347 patent represent a distinct improvement in the art, it has been found that the use of trailing spreader chains can sometimes fail to give complete and uniform coverage on a roofing deck.
There is accordingly a need in the art for an improved applicator/spreader device especially designed for roofing operations and which serves to evenly apply and spread viscous roofing materials over a variety of deck surfaces.